Break through bleeding means the pills are not working, and that you CAN get pregnant.
You indeed can become pregnant if you missed 3 pills and are bleeding. The reason you would be bleeding or maybe spotting is because you're not taking the pills. If you've missed 3 pills in one pack, you should throw that pack away and start a new pack and definitely use backup protection!
Birth Control pills are not long acting. That is why you have bleeding if you miss just 1 dose. If you have missed a week you can get pregnant. You will need to use a back up method until you can begin taking the pills again.
You should not be pregnant when you start taking the pills as you start taking them within a week of the start of your period and if you have a period you are 99.5% sure you are not pregnant. However if you are pregnant the pills will have no effect.
99% no if you are taking the rest of the pills on time and not have missed any.
No, pills do not cause pregnancy. Sex causes pregnancy.
According to AskDocWeb, breakthrough bleeding is bleeding that occurs during the time that you are taking the active pills, that is, at times other than during the placebo pills. This can occur when you are becoming adjusted to taking the pills for the first time or if you have been off them for a time and are beginning them again. This is usually an adjustment situation and not serious.
Breakthrough bleeding occurs when you stop taking BC pills. If it occurs while taking BC pills you will need to see your Doctor as the doseage may not be right for you.
Birth Control pills, ring, patch, DepoProvera and the IUD are not barriers.
When you want to get pregnant.
No u can't